2x a week for growth?

Is training each muscle group 2x a week the only way to incite growth? I've been doing so and I have to say it's wearing me out. I'm 39 and my program looks like this
Day 1 legs
Day 2 chest and shoulders
Day 3 back and arms
Day 4 rest
Then repeat the process. I'm looking to gain size after cutting down, but is it really necessary to train each group more than once a week? Does anyone have any other suggestions?

Is training each muscle group 2x a week the only way to incite growth? I've been doing so and I have to say it's wearing me out. I'm 39 and my program looks like this
Day 1 legs
Day 2 chest and shoulders
Day 3 back and arms
Day 4 rest
Then repeat the process. I'm looking to gain size after cutting down, but is it really necessary to train each group more than once a week? Does anyone have any other suggestions?

Looks like a good set up.
Undulate rep ranges and deload every 4-6 weeks.
Like mentioned above, regulating volume to avoid over fatigue.

Is training each muscle group 2x a week the only way to incite growth? I've been doing so and I have to say it's wearing me out. I'm 39 and my program looks like this
Day 1 legs
Day 2 chest and shoulders
Day 3 back and arms
Day 4 rest
Then repeat the process. I'm looking to gain size after cutting down, but is it really necessary to train each group more than once a week? Does anyone have any other suggestions?

Definitely not necessary. You need to find the right amount of work load that you can recover from. Alot of gaining muscle will also be dependent on your nutrition, especially coming off a cut.

The total volume per session (how many sets and reps you perform per workout) is a key driver in muscle growth. One issue is that people think “more equals better” but this isn’t always the case.

Based on the research, once you’ve done around 5 - 10 sets per muscle group, the body doesn’t require any further stimulus nor will it grow to any significantly greater extent. So, if you’re doing 20 sets for your chest once per week, the second half of your workout, or your last 10 sets, may be a waste of time and energy.

The stimulus your muscle needs for change can be achieved within 5 – 10 solid sets. Beyond that, the muscle is fatigued and the stimulus isn’t producing beneficial results.

Remember, by doing less sets per workout, such as 5 - 10, you can keep your energy level high on each set and perform it with 100% intensity. This will ensure you’re getting the most out of each set, rather than continuing to train a fatigued muscle at a low intensity.

Consider working muscle groups multiple times a week, but not all of them in the same week. For example, stick with your split, but do back multiple times in that week and do that for a few weeks. Then do the same with chest and then legs or whatever body parts you want to see the most improvement in.

Start with low volume, increase volume over time. Deload for 2-4 weeks when you can't complete your training and then start again with a lower volume.
Increase or decrease frequency every other deload. Or spend 4 weeks higher frequency for one body part, then switch to another

If you're not gaining muscle and not getting fatter either, you're probably not eating enough

I am a carnivore (diet based exclusively on meat)- Here is my diet and training log
http://anabolicminds.com/forum/workout-logs/303950-im-carnivore.html

Start with low volume, increase volume over time. Deload for 2-4 weeks when you can't complete your training and then start again with a lower volume.
Increase or decrease frequency every other deload. Or spend 4 weeks higher frequency for one body part, then switch to another

If you're not gaining muscle and not getting fatter either, you're probably not eating enough

In regards to training frequency also consider the more you practice something the better you get at it. I find I maintain a stronger mind/muscle connection when training muscles multiple times a week. Let's say you squat every single day. After a few weeks you'll be amazed how much better you'll get even if you've been squatting for years.